The present invention relates to methods and compositions of stabilizing a surface within a subterranean formation or fracture. More particularly, the present invention relates to stabilizing surfaces within a subterranean formation or fracture using particulates coated with a consolidating liquid.
Hydrocarbon-producing wells are often stimulated by hydraulic fracturing treatments. In hydraulic fracturing treatments, a viscous fracturing fluid, which also functions as a carrier fluid, is pumped into a producing zone at a rate and pressure such that one or more fractures are formed in the zone. Typically, particulates, such as graded sand, suspended in a portion of the fracturing fluid are then deposited in the fractures when the fracturing fluid is converted to a thin fluid to be returned to the surface. These particulate solids, or “proppant particulates,” serve to prevent the fractures from fully closing so that conductive channels are formed through which produced hydrocarbons can flow.
Proppant particulates deposited in the fractures have been coated with hardenable resins or tackifying agents in order to prevent or reduce the subsequent flowback of proppant particulates and/or other particulates with the produced fluids. These coatings help to consolidate the proppant into a hard, permeable pack while allowing small amounts of deformation at the surface of the proppant packs to reduce the effects of point loading and/or to reduce proppant crushing.
Most proppant pack treatments have focused on consolidating the proppant pack itself, neglecting the importance of the interaction between the mechanical properties of the subterranean formation in which the proppant pack is placed and the proppant pack. These interactions can have a dramatic effect on overall fracture conductivity as well. In particular, under high stress and/or high flow conditions, formation material can intrude into the proppant pack, potentially damaging the pack. The intrusion of formation material into the proppant pack can also increase the amount of point loading and/or proppant crushing experienced by the proppant pack. These phenomena can reduce the overall conductivity of the propped fracture and/or the permeability of the proppant pack, which may negatively affect the production of the well.